Constellations by month

Constellations of December

The eight constellations at their best in December are Aries, Cetus, Eridanus, Fornax, Horologium, Hydrus, Perseus and Triangulum. The charts show the whole sky at 9 pm on December 15 from 40°N and 35°S. The Geminids and Ursids peak this month.

The sky at 9 pm in mid-December from 40°N CETUS ERIDANUS PERSEUS ARIES FORNAX TRIANGULUM URSA MAJOR PEGASUS DRACO AQUARIUS PISCES CYGNUS TAURUS CAMELOPARDALIS ANDROMEDA AURIGA CASSIOPEIA ORION CEPHEUS LYNX GEMINI CANCER MONOCEROS SCULPTOR LEPUS URSA MINOR LACERTA CANIS MINOR EQUULEUS N S E W
From 40°N (the United States, southern Europe, northern China, Japan). North at top; turn the chart so the direction you face is at the bottom.
The sky at 9 pm in mid-December from 35°S CETUS ERIDANUS PERSEUS ARIES FORNAX HOROLOGIUM HYDRUS TRIANGULUM PEGASUS AQUARIUS PISCES SAGITTARIUS TAURUS PUPPIS AURIGA ORION VELA CARINA MONOCEROS SCULPTOR PHOENIX CAPRICORNUS CANIS MAJOR PAVO GRUS TUCANA INDUS OCTANS LEPUS COLUMBA TELESCOPIUM PICTOR PISCIS AUSTRINUS ARA PYXIS MICROSCOPIUM APUS CANIS MINOR MENSA VOLANS MUSCA CAELUM TRIANGULUM AUSTRALE CIRCINUS S N W E
From 35°S (Sydney, Cape Town, Buenos Aires). South at top; the center is overhead and the rim is the horizon.

Bright lines and names: constellations at their best in December. Gold dashes: the ecliptic, where the Moon and planets travel. 9 pm local standard time on December 15; the same view comes an hour earlier at the end of the month and an hour later at the start. Click a name to open its chart.

Aries, Cetus, Eridanus, Fornax, Horologium, Hydrus, Perseus and Triangulum are at their best in December

A constellation is at its best when it stands highest in the evening, due south from the northern hemisphere or due north from the southern. The last two columns give its height above the horizon at 9 pm in mid-December.

ConstellationMeaningHemisphereBrightest starMessierAt 40°NAt 35°S
AriesRamNorthernHamal72°33°
CetusWhaleSouthernDeneb Kaitos144°59°
EridanusRiverSouthernAchernar31°69°
FornaxFurnaceSouthernAlpha Fornacis22°83°
HorologiumClockSouthernAlpha Horologiibelow horizon71°
HydrusWater SnakeSouthernBeta Hydribelow horizon53°
PerseusHero (son of Zeus)NorthernMirfak269°6°
TriangulumTriangleNorthernBeta Trianguli179°20°

Constellations more than 20° high at 9 pm in December

Measured at the center of each constellation. Large constellations can be partly visible when their center is lower.

From 40°N: 20 constellations

From 35°S: 32 constellations

Meteor showers peaking in December

Rates are the zenithal hourly rate, the count one observer would see under a dark sky with the radiant overhead; real counts are lower. Peak dates move by about a day from year to year.

ShowerPeakActiveRate per hourRadiantParent body
GeminidsDec 14Dec 4 - Dec 20150Gemini3200 Phaethon (asteroid)
UrsidsDec 22Dec 17 - Dec 2610Ursa Minor8P/Tuttle
Puppid-VelidsDec 7Dec 1 - Dec 1510Vela
sigma HydridsDec 9Dec 3 - Dec 207Hydra
Comae BerenicidsDec 23Dec 4 - Jan 303Leo
December MonocerotidsDec 9Dec 1 - Dec 193MonocerosC/1917 F1 (Mellish)
PhoenicidsDec 2Dec 1 - Dec 5Sculptor289P/Blanpain

Video: December stargazing

December Stargazing: Constellations & Meteor Showers · Watch on YouTube

Constellations month by month

← November · January →